1. Field of Invention
The present invention relates to an electro-optical element and a method for manufacturing an electro-optical element, an optical module and a method to drive an optical module.
2. Description of Related Art
A related art light-emitting element, for example, a surface emitting semiconductor laser is disclosed in Japanese Unexamined Patent Publication Application No. 10-135568. Generally, if a light-emitting element is used for optical communication, optical arithmetic or a light source for various kinds of sensors, an optical characteristic of an emitted light, for example a radiation angle or a wavelength of light, requires control.
In the above related art light-emitting element, a light-detecting part is stacked on the light-emitting element. This light-detecting part receives a part of the light emitted from the light-emitting element, thereby detecting its light volume. Therefore, a diameter of the light-detecting part is made smaller than that of a light-emitting region of the light-emitting element so that part of the light emitted from the light-emitting element can be introduced into the light-detecting part.
In the above related art light-emitting element, the light-detecting part can be used as a normal light-receiving element, instead of or in addition to, its usage to monitor the power of light generated in the light-emitting element. In this case, as mentioned above, the diameter of the light-detecting part is generally made smaller than that of the light-emitting region of the light-emitting element part. However, this results in the light receiving area of the light-detecting part being too small thereby causing insufficient sensitivity.